golang.org/toolchain@v0.0.1-go1.9rc2.windows-amd64/src/cmd/vendor/github.com/google/pprof/internal/proftest/proftest.go (about)

     1  // Copyright 2014 Google Inc. All Rights Reserved.
     2  //
     3  // Licensed under the Apache License, Version 2.0 (the "License");
     4  // you may not use this file except in compliance with the License.
     5  // You may obtain a copy of the License at
     6  //
     7  //     http://www.apache.org/licenses/LICENSE-2.0
     8  //
     9  // Unless required by applicable law or agreed to in writing, software
    10  // distributed under the License is distributed on an "AS IS" BASIS,
    11  // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    12  // See the License for the specific language governing permissions and
    13  // limitations under the License.
    14  
    15  // Package proftest provides some utility routines to test other
    16  // packages related to profiles.
    17  package proftest
    18  
    19  import (
    20  	"encoding/json"
    21  	"fmt"
    22  	"io/ioutil"
    23  	"os"
    24  	"os/exec"
    25  	"testing"
    26  )
    27  
    28  // Diff compares two byte arrays using the diff tool to highlight the
    29  // differences. It is meant for testing purposes to display the
    30  // differences between expected and actual output.
    31  func Diff(b1, b2 []byte) (data []byte, err error) {
    32  	f1, err := ioutil.TempFile("", "proto_test")
    33  	if err != nil {
    34  		return nil, err
    35  	}
    36  	defer os.Remove(f1.Name())
    37  	defer f1.Close()
    38  
    39  	f2, err := ioutil.TempFile("", "proto_test")
    40  	if err != nil {
    41  		return nil, err
    42  	}
    43  	defer os.Remove(f2.Name())
    44  	defer f2.Close()
    45  
    46  	f1.Write(b1)
    47  	f2.Write(b2)
    48  
    49  	data, err = exec.Command("diff", "-u", f1.Name(), f2.Name()).CombinedOutput()
    50  	if len(data) > 0 {
    51  		// diff exits with a non-zero status when the files don't match.
    52  		// Ignore that failure as long as we get output.
    53  		err = nil
    54  	}
    55  	if err != nil {
    56  		data = []byte(fmt.Sprintf("diff failed: %v\nb1: %q\nb2: %q\n", err, b1, b2))
    57  		err = nil
    58  	}
    59  	return
    60  }
    61  
    62  // EncodeJSON encodes a value into a byte array. This is intended for
    63  // testing purposes.
    64  func EncodeJSON(x interface{}) []byte {
    65  	data, err := json.MarshalIndent(x, "", "    ")
    66  	if err != nil {
    67  		panic(err)
    68  	}
    69  	data = append(data, '\n')
    70  	return data
    71  }
    72  
    73  // TestUI implements the plugin.UI interface, triggering test failures
    74  // if more than Ignore errors are printed.
    75  type TestUI struct {
    76  	T      *testing.T
    77  	Ignore int
    78  }
    79  
    80  // ReadLine returns no input, as no input is expected during testing.
    81  func (ui *TestUI) ReadLine(_ string) (string, error) {
    82  	return "", fmt.Errorf("no input")
    83  }
    84  
    85  // Print messages are discarded by the test UI.
    86  func (ui *TestUI) Print(args ...interface{}) {
    87  }
    88  
    89  // PrintErr messages may trigger an error failure. A fixed number of
    90  // error messages are permitted when appropriate.
    91  func (ui *TestUI) PrintErr(args ...interface{}) {
    92  	if ui.Ignore > 0 {
    93  		ui.Ignore--
    94  		return
    95  	}
    96  	ui.T.Error(args)
    97  }
    98  
    99  // IsTerminal indicates if the UI is an interactive terminal.
   100  func (ui *TestUI) IsTerminal() bool {
   101  	return false
   102  }
   103  
   104  // SetAutoComplete is not supported by the test UI.
   105  func (ui *TestUI) SetAutoComplete(_ func(string) string) {
   106  }